Research Of Driver For LED Street Lamp Based On LCLC Resonant Converter

The lighting industry is booming,and its energy consumption is huge.The light-emitting diode(LED)is characterized by high luminous efficacy of light source,low cost,energy conservation and environment protection.It can alleviate energy source problems to a large extent.It will gradually replace the traditional light source and become the core of the lighting industry.The LED cannot be driven by the 50 Hz AC Power supply directly,and it needs a high efficiency and stable dc driver supply to ensure its excellent performance.There are many kinds of LED driver,but most of them cann’t meet the requirements because of low power level,large volume and low efficiency.In this paper,a high power LED driver based on LCLC resonant converter is proposed.The LED driver consists of three stages.The design analysis of each stage and optimization of the topology is done.The development status of high power LED driver is studied,and a three-stage LED driver is designed.In order to ensure high power factor,the most mature BOOST power factor correction circuit is selected as the first stage.In order to improve the topology efficiency,a half-bridge LCLC resonant converter is selected as the intermediate stage,which can realize ZVS and ZCS at the same time.The working state under different modes of the topology is analyzed.The gain of topology and the dead-time of two MOSFET are derived.The parameters of four resonant components are obtained through theoretical analysis and experimental optimization,and the simulation analysis and experimental verification are carried out.In order to keep the LED strings’ currents as same as possible,a mixed current sharing method based on capacitance is proposed.The theoretical analysis,simulation analysis and physical experiment verification are carried out to ensure the feasibility of the current sharing topology.According to the former two stage,the paper proposes the idea of sharing MOSFET of PFC and LCLC resonant topology to reduce the numbers of the components.Detailed analysis,simulation experiment of the topology integration process is carried out.Thermal analysis of the LED wafer is carried out by the COMSOL and the LED load is made.The influence of different winding methods on magnetic inductance and leakage inductance of isolated transformer is studied and the isolated transformer is made.The whole topology of three-stage LED driver is simulated,and the feasibility and efficiency of this design are verified by experiments.Finally,based on the background of practical application,the production of LED lamps is made.The test result indicates that the LED light has a high brightness and wide range of illumination meet the road lamp lighting requirements.